NFL vice president of officiating Dean Blandino put his stamp of approval on the referees' decision to pick up a pass interference flag in the end zone on the final play of the New England Patriots' 24-20 loss to the Carolina Panthers on Monday night, saying they used "proper mechanics" to make a "tight judgment call."

The game ended on a throw from Tom Brady to tight end Rob Gronkowski in the back of the end zone that was intercepted as time expired. Gronkowski appeared to have been held by linebacker Luke Kuechly on the play. A flag was thrown, but after a conference with the other officials, referee Clete Blakeman announced there was no penalty on the play. Had the penalty been upheld, the Patriots would have had one untimed play from the 1-yard line to try and score the winning touchdown.

The Rule In Question

Monday night's officials determined there was no chance for tight end Rob Gronkowski to catch the last pass thrown by Tom Brady. Here is the rule in question:

Rule 8, Section 5, Article 3
Permissible Acts

Article 3 Permissible Acts by both teams while the ball is in the air. Acts that are permissible by a player include, but are not limited to:

(c) Contact that would normally be considered pass interference, but the pass is clearly uncatchable by the involved players, except as specified in 8-3-2 and 8-5-4 pertaining to blocking downfield by the offense.

Blandino drew a key distinction between a defensive player making contact with an opponent and "restricting" him.

"The issue isn't the contact [between Kuechly and Gronkowski], the issue is the restriction and does it occur prior to the ball being touched," Blandino explained Tuesday during his segment on the NFL Network. "At full speed the officials made a tight judgment call and they determined that the restriction occurred just as the ball was being touched [by Panthers safety Robert Lester]. Again, at full speed you can see why they made that call."

Pass interference penalties are not reviewable, which means the officials had to make a judgment call on when the contact Kuechly was making with Gronkowski became "restrictive." In their judgment, Blandino said, they ruled that the "restriction occurred simultaneously with the ball being touched. When you watch it at full speed you can see why they would make that call on the field."

Following the game, Blakeman defended the decision, saying Gronkowski's distance from the ball rendered the pass uncatchable and there was "a determination that, in essence, uncatchability -- that the ball was intercepted at or about the same time the primary contact against the receiver occurred."

Less than 12 hours after the non-call cost his team a shot at winning the game, Patriots coach Bill Belichick was not any more inclined to discuss the play than he was following the contest.

"Whatever the officials think is the only thing that matters," Belichick said Tuesday on a conference call with reporters. "They're the ones that make the calls. It's their explanation and their judgment that we all have to abide by."

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Blakeman was followed off the field by an irate Brady, who gave the official an earful but was more measured in his comments at a postgame news conference.

"I wish it wouldn't come down to that," Brady said. "I think there are plenty of plays we could have made. But it did, and they are going to make a call or they are not going to make a call. ... We can play better than that."

Gronkowski was asked if he felt he was held on the play, and he responded, "I've gotta rewatch, but if you saw that, then I would say yeah."

Kuechly said his focus was on Gronkowski and therefore didn't see Brady release the ball.

"Honestly, I didn't see the throw," Kuechly said. "I didn't see where the ball ended up. I just saw his eyes get big and his hands go up. When that happens, the ball is going to him. I didn't see what happened after the play. I just knew there was a flag down, a bunch of people around the refs. They waved it off and the crowd cheered."

Panthers coach Ron Rivera said Tuesday that he is fine with the way the game ended.

"We've been on the other end of those calls too, as well," Rivera said. "As far as I'm concerned, that was the decision -- the decision we live with. No matter how much people want to talk about it and rehash, rehash, it's not going to change."

Rivera acknowledged, however, that he would have felt differently if the Panthers (7-3) were on the other end of a similarly controversial call.

"Without a doubt -- it's human nature," he said. "You want the good things, the right things, things that you believe are correct."

Information from ESPN.com Patriots reporters Mike Reiss and Field Yates and ESPN.com Panthers reporter David Newton contributed to this report.